[Leet Code] Longest Continuous Increasing Subsequence
2 min readDec 23, 2020
Problem:
Given an unsorted array of integers nums
, return the length of the longest continuous increasing subsequence (i.e. subarray). The subsequence must be strictly increasing.
A continuous increasing subsequence is defined by two indices l
and r
(l < r
) such that it is [nums[l], nums[l + 1], ..., nums[r - 1], nums[r]]
and for each l <= i < r
, nums[i] < nums[i + 1]
.
Example 1:
Input: nums = [1,3,5,4,7]
Output: 3
Explanation: The longest continuous increasing subsequence is [1,3,5] with length 3.
Even though [1,3,5,7] is an increasing subsequence, it is not continuous as elements 5 and 7 are separated by element
4.
Example 2:
Input: nums = [2,2,2,2,2]
Output: 1
Explanation: The longest continuous increasing subsequence is [2] with length 1. Note that it must be strictly
increasing.
Constraints:
0 <= nums.length <= 104
-109 <= nums[i] <= 109
Solution:
class Solution(object):
def findLengthOfLCIS(self, nums):
"""
:type nums: List[int]
:rtype: int
"""
last_number = 0
counter = 0
max_counter = 0
for i in range(len(nums)):
if i == 0 or len(nums) == 0:
counter = 1
elif nums[i] > last_num:
counter += 1
else:
counter = 1
if counter >= max_counter:
max_counter = counter
last_num = nums[i]
return max_counter